Studies will be initiated as to the basic biochemistry of human basophilic leukocyte constituents; particularly, the nature of the glycosaminoglycans and the presence/absence of plasminogen activator activity. The collaborations with Dr. Askenase using our highly specific anti-basophil serum will attempt to evaluate the role of basophils in a cell-mediated immune system to ticks. This system is convenient because the end-point is obtained rather quickly (within a day), unlike allograft or tumor rejection where multiple doses of precious serum would have to be given over a period of 7 days. Basic studies involing surface and granule proteases of guinea pig basophils with particular reference to cytochemical approaches at the electron microscopic level.